Hardness tester



March 6, 1951 w. A. WILLIAMS 2,544,205

` HARDNEss TESTER i"y Filed Aug. 7, 1947 27a 25a 23a Vg S2 Ilm! h 4 25a Jgd WITNESSES: INVENTOR- Z/md K mlilmfLw/mm,

BY @we @MQ w n Y ATTORNEYS.

Patented Mar. 6, 1951 HARDNESS TESTER William A. Williams, Philadelphia, Pa., assgnor to The American Pulley Company, Philadelphia, Pa., a, corporation of Pennsylvania Application August "7, 1947, Serial No. 767,244 s claims. (c1. 'vso-s1) This invention relates to devices useful in testing the hardness of metals and other materials. The chief aim of my invention is to provide a device of the kind referred to which is light and compact so that it may be easily carried about and directly applied to the specimens to be tested; which can be used to test the outer surfaces of solid specimens as well as the interior surfaces of hollow specimens; which is simple in construction and operation which can be relied upon fori accuracy; and which moreover lends itself to ready production in quantity at relatively small cost.

Other objects and attendant advantageswill appear from the following detailed description of the attached drawings, wherein Fig. 1 is a View in side elevation, of a hardness tester conveniently embodying my invention in one form and showing how the same is applied in testing.

Fig. 2 is a view partly in elevation and partly in section taken as indicated by the angled arrows II--II in Fig. 1.

Fig. 3 is a fragmentary view in section taken as indicated by the angled arrows III-III in Fig. 2; and

Fig. 4 is a fragmentary View in elevation taken as indicated by the angled arrows IV-IV Vin Fig. 2.

As herein illustrated, my improved hardness tester comprises a holding element Illa in the form of a permanent horseshoe magnet whereof the pole ends are abutted against the surface of the specimen S2 which is to be tested. The pole ends of the holding element la are lrounded as shown and one of them is bifurcated as indicated at 60 in Fig. 2 so that the specimen is contacted atthreev points. By virtue of this construction, accurate tests may be made of specimens whereof the surfaces are undulated or uneven. The holding element Illa has a central transverse bore lil into which is tted atube 62 of non-magnetic metal such as brass or bronze, said tube having a circumferential stop flange 63 between which and the bottom of the counter bore in the top of said holding element, the anchorage end of a bracket 40a is interposed. The lower end of the tube 62 is externally threaded for engagement by a nut 65, and the upper end tapered and split and likewise externally threaded for engagement by a nut BB. As shown, the tube 62 is internally threaded at its upper end to serve as a bearing centrally over the gap in the magnet lila for a screw adjusting element a. Aiixed to the free end of the arm a of the spring element 29a is a load gauge 38a of a conventional type whereof the actuating plunger 39a contacts the end of arm 3| a of said spring element. The dial of the gauge 38a is graduated to indicate loads in kilograms, and shown in Fig, 2 `has special markings designated Set, 15 KG, 30 KG, and 45 KG, in addition to a zero mark, for a purpose also later on explained. The lower end of the adjusting element 25a. is plain cylindrc and extends into the socket 33a in the upper arm 3 la of a horizontally arranged spring element 29a of hair pin configuration, it being held in said socket by a key 35a which passes into a circumferential groove 35a thereof. A ball 31a is interposed between the lower end of the adjusting element 25a and the bottom of the socket 33a in the arm 3IaA ofthe spring element 29a to reduce friction and ease operation. To the extreme tapered upper end of the adjusting element 25a is secured, by means of screw 21a, a manipulating hand wheel 28a having a pendent axial sleeve extension 61 which, with interposition of an annular clearance, surrounds the upper projecting portion of the tube 62. Mounted on the lower end of the sleeve extension 61 of hand wheel 28a is a collar 42a with peripheral graduations 45a for coordination with a marker 46a on a transparent upward projection lla on bracket 40a. A stud 43a on collar 42a is arranged to cooperate with the projection Ma to restrict rotation of the adjusting element 25a, to a single turn. The collar 42a is held in position by a spring-pressed ball 6B which fits into a circumferential groove 69 in the sleeve extension 61 of hand wheel 28a. A penetrating element Illa is screwed into the lower arm 30a of n spring element 29a, with the actuating plunger 39a bearing upon the other arm 3 la of said spring element. Rotation of the spring 'element 29a within the bight of the magnet |0a is prevented through engagement of a stud 1D thereon in a slot 'H in the down-turned end of a stop arm 'l2 integrally formed on the bracket 49a, as shown in Figs.`2 and 4.

In order to facilitate dislodgment of the tester after a test has been completed, I have provided means including straps l5 of non-magnetic material which-conform to and are suitably secured to the arcuate inner surface of magnet Ilia, and which have; lateral projections 16 and Tl in a plane above the pole faces as shown in Figs. 6 and '7. Threadedly engaged in the projections 16 and 11 are thumb screws 18 and 19 capable, in being turned, of reacting with the the screws 'I8 and 19 are backed oi to the point beyond the plane of the pole ends of magnet Illa as shown in Fig. 1 so that said pole ends can bear directly upon the surface of the specimen S2. While in Figs. 1 and 3 I have shown the holding element Illa as having the form of a permanent horseshoe magnet, it will be obvious that an electromagnet may be substituted therefor with-n out @harige inthe operation f 'functioning'. of the other elements of the tester. When an electromagnet is used, the dislodgment means above. described can of course be dispensed with, since; upon interruption of current flow to the vcoil'r coils of such a magnet, the residual flux will be.. insuiicient in power to prevent ready removal of the tester from the specimen. after a test'has. been made.

In the use of the tester, the hand Weel 28a is turned to bring the point 19a into contact 4with. the specimen 52 and until the pointer of gauge iia registersfffSet,` whereuponk the collarr (tia,I is` rotativtly shifted on sleeve 6 1, so that its'zerlo, graduation coincides with themaricer lita@ Thereuponl the hand'weeiZSa, is further turned until the gauge pointerregjisters successiv at l5 KG, 30 KG and 45 'KG with interruptions at each stage for ascertaininent of thef'correspo'nd ies fier-rh registrati@ readings@ SealeiiSg-f Havingthus. desieribed my irri/erlebe 'lairrl- 1. In a hardness tester for testingtheh d .i of magnetizable metals, av holding element n the. form of a magnet with spaced'c'o-'plan faces capable. f tehrprary tiehmelt't I face of the specimenA tdbe testedanwl" for penetrating ths trae@ or the, ,seen a regulabble Giustina elrriem 'r'gaeedre the", holding element'medially.btwentiiey ple fends a`spiinge1'em'ent`r`it` posedlbetweenfand con; necting the. penetrating element andthe adj t,- ingv element; 4'a''loadindic'ating guage actuated 'tl'irouglf'iV flexure of the elrril? 'as' the (adi justing element is rg'ulate'dj4 anda depth'pene'; tration indicating means'opera'td throgl' movj ment' ofsaid adjusting element."

21A hardness testerfaccording to claim 1, fuir,-l ther including means on'the holding element' at its,` 1101 endsoperabl byreactiofnu'pon' 'the ec; iniento assist in Sldgng the tester 1afverfa testis completed'. 3. A hardness tester according to claim 1, fun-A ther including thumb screws'on' the hfqldngfeiaf nient adjacent its 'pole' ends capableo'i 'reacting upon' the specimen' to assistin'dislodging the tester after a testis ccm'plet'df' j fl.' A'hardness'testr"'accrding toA claini 1,

Iwherein the 'adiusting lementl'is in theffrm 6i Shrew. threadedlyeriggd. fp L through the arch ci the 'magnet at the' ce er a d previdednwith manipf111ating'-hand wheel# are wherein aaargh weer naarmate the magnet for coordination with" giadations lcircunfiferentially ci the adjusting elementiWM 5. A hardness tester according 'to'claim 1, wherein the adjusting element is in theforn of a screw threadedly engaged in and passing 'down ierevrh a eee-reageer@ behi Sesfrd 'iria 4 radial bore through the arch of the magnet at the center, said bushing being prolonged upward beyond the top of the magnet and said screw having, at its upper end, a manipulating hand wheel with a tubular hub extending down over the projecting portion of the bushing; and wherein the depth penetration indicating means includes a marker which is xedly secured to the'bushing, and a collaronthe tubular` portion of the wheel hub with graduations on its periphery for coordination with the marker.

6, A hardness tester according to claim l, wherein the adjusting element is in the form of a screw. threadedlyy engaged in and passing down through Aa non-'magnetic bushing secured in a radial bore through the arch of the magnet at the l of with a circumfe-rentialgroove in the tubu r center, said bushing being prolonged upward bey'rd""'th"top"'f"the magnet and said screw having, at its upper end, a manipulating hand wheel with a tubular hub extinding down over the. projecting portion Qf. the. bushing; and Wherenfhe'ptfnntrtion imitating rras i111-, clud @marker which uiS fixedlsf'securd 't6 the uhina' and, a' Cellar' heljd in place through, @ne sagement Of a Sprihg-biasedball internally there;

portion of the wheelv hub, 'and lhaving circumf ie'rential graduations fory coordination with the marker' A 7L`Iri 'a hardness tester for testing the hardness. of magnengapie aimais, a holding eiemeitfir @ne form cfa magnet adapted to attach itself' t they surface' f meneame' specimen t6 be tested; al point element for penetrating the surface'of 'th' speci rfa]regulat'abl adjusting screw element tatlve inabaringcntallyover a gap'it'e magnet; an interposedspring element'c'ronn'e'c'tfr ing the penetrating -element' Awith' 'the a'dj ng; lrnt; a"162541`"fdi'atlg` gl'i'lfge` 'actua YEl througlileiiuf of the Spring Y'element' as 'the 'faldf jstilg'elent regulated faa depth pener trati indicatihgman'sAperatd thrpigh' mvl ment of the adjusting elementI Sfg"h l'ardnssV testuaoding to claim 7, further including means n the holding 'eifr'nent operable by reaction upon the specimen, to sist disidgvilg' the t'e'st'raftr'a test is pinplete A .l

WQLlVI-,Sf REFEIENCES CITED The following references are of record in the @this UNiTED STATES PATENTS 

